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UK-facing delivery, aligned to UK working hours and UK filing deadlines

B4ES

Tax & Compliance

Corporation Tax & Computations

Corporation tax preparation done properly is not a mechanical exercise. Marginal relief, associated companies, capital allowances and loss planning all carry judgement — and all are routinely missed when the computation is squeezed in after a late set of accounts.

  • Accountancy practices

The problem

Reliefs left on the table

When the computation is the last thing done before a filing deadline, it gets done narrowly. Full expensing goes unclaimed, structures and buildings allowance is overlooked, group relief is not modelled, and the client pays more than they needed to — which is a fee conversation nobody enjoys having a year later.

  • Associated company rules affect the marginal relief limits and are easy to get wrong.
  • Capital allowance claims need a fixed asset review, not a copy-forward.
  • Loss relief options need modelling before the return is filed, not after.

At a glance

Service line
Tax & Compliance
Delivered for
Accountancy practices
Typical cadence
With accounts — Prepared alongside the year-end file so the two reconcile before either leaves us. Standalone — Three to five working days where accounts are already finalised.
Engagement models
Available per job, on ad-hoc hours, or through a dedicated resource. Compare models.

Scope

What we prepare

Scope is agreed in writing before work starts and reviewed at each service review. Anything outside it is quoted separately rather than absorbed quietly and invoiced later.

Returns

  • CT600 with all relevant supplementary pages
  • iXBRL-tagged computations and accounts for HMRC submission
  • Short and long accounting period apportionment
  • Amended returns and overpayment relief claims

Computations

  • Full tax computation with adjustments to profit clearly evidenced
  • Capital allowances — full expensing, annual investment allowance, main and special rate pools
  • Structures and buildings allowance schedules
  • Marginal relief with associated company analysis
  • Loss utilisation: carry-back, carry-forward, group and terminal loss relief
  • Directors' loan account s455 charges and relief tracking
  • Transfer pricing and disallowed expenditure schedules

Claims support

  • R&D tax relief claim preparation support, including the additional information form
  • Patent box computation support
  • Creative sector relief claims
  • Quarterly instalment payment calculations for large companies

Software

Platforms we work in for this service

We work inside your existing systems under named user accounts. If your stack is not listed, tell us — we will confirm honestly whether we can support it immediately or need a ramp-up period.

  • IRIS Business Tax
  • TaxCalc
  • CCH Corporation Tax
  • Alphatax
  • Digita
  • Capium

The boundary

What stays with your firm

This matters more than the task list. A delivery partner that blurs this line creates regulatory exposure for you, so we state it explicitly on every engagement.

Yours, always

  • The client engagement and engagement letter
  • Professional judgement and final review
  • Sign-off, submission authority and the fee
  • Client advice and the client relationship

Ours

  • Preparation, processing and documentation
  • Internal second-person review before release
  • Turnaround against the agreed timetable
  • Rework at our cost where the error is ours

Questions

Corporation Tax — what firms ask

All FAQs
Do you prepare R&D claims?

We prepare the computational and documentary elements of a claim, including the additional information form. The technical narrative and the professional judgement on whether the work qualifies stay with your firm — that judgement carries risk that only your engagement should hold.

Are computations reviewed before they reach us?

Always, by a second preparer against a standard checklist covering associated companies, capital allowances, loss position and s455. The completed checklist comes with the file.

Next step

Talk to us about corporation tax.

Bring a real example — a live job, a difficult client file, a cycle you are behind on. A concrete case tells you far more about a provider than a capability slide ever will.

What to expect

  • No obligation and no minimum commitment to talk
  • A written proposal within five working days
  • A paid pilot before any long-term arrangement
Prefer email? hello@b4es.co.uk